WASHINGTON (CNN) --Former Vice President Al Gore accused the Bush administration Sunday of using the war on terrorism "to consolidate its power and escape any accountability for its use."

Gore said that though the threat of terrorism and the potential use of weapons of mass destruction required speedy action by the executive branch, "President Bush has stretched this new practical imperative way beyond what is healthy for our democracy."

Gore said the Bush administration has sought "to rule by secrecy and unquestioned authority," and he accused Republicans in Congress of aiding the White House by threatening to shut down investigations over political disputes.

"They have taken us much farther down the road toward an intrusive, Big Brother-style government -- toward the dangers prophesied by George Orwell in his book '1984' -- than anyone ever thought would be possible in the United States of America," Gore said.

He said Bush has tried to maximize his power by emphasizing his role as commander in chief of the armed forces, "conflating it with his other role as head of government and head of state, and especially with his political role as head of the Republican Party."

Gore, who lost the disputed 2000 presidential race to Bush, spoke to about 2,500 members of two liberal advocacy groups, the American Constitution Society and Moveon.org.

He called for a repeal of most of the USA Patriot Act, saying its few useful provisions are far outweighed by those he said are impinging on American freedoms.

Passed overwhelmingly by Congress after the terrorist attacks of September 11, 2001, the act gave the government more powers of surveillance and detention, even permitting authorities to keep tabs on what people read and to conduct searches in secret.

"It makes no more sense to launch an assault on our civil liberties as the best way to get at terrorists than it did to launch an invasion of Iraq as the best way to get at Osama bin Laden," Gore said.

In each case, he said, "the administration has attacked the wrong target."

He accused the Bush administration of seeking to expand government surveillance powers, to politicize law enforcement, and to straight-arm both congressional oversight and the independent commission investigating the September 11 attacks.

"Under the rubric of protecting national security, they have obtained new powers to gather information from citizens and keep it secret," Gore said.

"Yet at the same time, they themselves refuse to disclose information that is highly relevant to the war against terrorism. They are even arrogantly refusing to provide information about 9/11 in their possession to the 9/11 commission."

The commission announced Friday it would subpoena the Pentagon for records of the North American Aerospace Defense Command and other Air Force commands on that day.

The panel, which must complete its investigation by May, is also debating whether to subpoena other government bodies, including the White House.

The commission, created by Congress, wants access to Bush's daily briefings and other sensitive intelligence documents in the weeks before the attacks.

The White House says the documents should not be put at risk of being released to the public.

Gore said the detentions of large numbers of immigrants after September 11 did little to aid security, but they did stir resentment in their communities and countries of origin.

Meanwhile, he said the administration had taken few steps to protect domestic infrastructure such as ports or power grids from possible terrorist attacks.

He criticized the designation of U.S. citizens as enemy combatants held without judicial review, and the imprisonment of detainees in the war on terrorism at the U.S. naval base at Guantanamo Bay, Cuba, urging that they receive similar hearings.

"If we don't provide this, how can we expect American soldiers captured overseas to be treated with equal respect?" he asked.

Gore opened the speech with a bit of humor, describing himself as a "recovering politician" and poking fun at the administration.

But the address quickly turned serious and sometimes heated, with the former vice president asking the audience to chime in occasionally.

As the speech came to a close, he asked, "So what should be done?"

"Run Al, Run," audience members cheered. Gore shook his head and went back to the speech.

The American Constitution Society is a national organization of law students, law professors, practicing lawyers and others that it says seeks to counter what it describes as the narrow, conservative vision that dominates American law today.

Moveon.org's goal is to "bring ordinary people back into politics," according to a statement on its Web site. It claims more than 2 million online activists.

One of its components is a political action committee that contributes money to candidates' campaigns. Earlier this year, it held an online primary in which former Vermont Gov. Howard Dean finished first.